<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta
        name="viewport"
        content="width=device-width, initial-scale=1.0"
    >
    <title>AJAX POST 请求</title>
    <style>
        #result {
            width: 200px;
            height: 100px;
            border: solid 1px #903;
        }
    </style>
</head>

<body>
    <div id="result"></div>

    <script>
        //获取元素对象
        const result = document.getElementById("result");
        //绑定事件 鼠标移动到上面
        result.addEventListener("mouseover", function () {
            // console.log("test");
            //1. 创建对象,发送请求
            const xhr = new XMLHttpRequest();
            //2. 初始化 设置请求类型与URL
            xhr.open('POST', 'http://127.0.0.1:8000/server');
            //设置请求头
            xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
            //设置自定义请求头
            xhr.setRequestHeader('name', 'superLmk');

            //3.发送
            xhr.send('a=100&b=200&c:300');
            // xhr.send('a:100&b:200&c:300');
            // xhr.send('123456654123');
            //4. 事件绑定
            xhr.onreadystatechange = function () {
                //判断
                if (xhr.readyState === 4) {
                    if (xhr.status >= 200 && xhr.status < 300) {
                        //处理服务端返回的结果
                        result.innerHTML = xhr.response;
                    }
                }
            }
        }) </script>
</body>

</html>